


Heard on High

by iberiandoctor (Jehane)



Series: Christmas in Metropolis, Christmas in Gotham [2]
Category: DC Extended Universe, DCU (Comics)
Genre: Animal Dicks, Christmas fic, Christmas in Gotham, Cluelessness, M/M, Mammalian Reproductive Behaviour, Mutual Pining, Porn With Plot, Second Time, aerial sex
Language: English
Status: Completed
Published: 2019-12-16
Updated: 2019-12-16
Packaged: 2021-02-26 01:47:38
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,390
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21745507
Author URL: https://archiveofourown.org/users/Jehane/pseuds/iberiandoctor
Summary: Above the rooftops of Gotham City this season lurks a thing with wings and hope.
Relationships: Clark Kent/Bruce Wayne
Series: Christmas in Metropolis, Christmas in Gotham [2]
Series URL: https://archiveofourown.org/series/1567273
Comments: 8
Kudos: 138
Collections: DC Universe, Spicy Advent - Multi-fandom Porn Advent Calendar 2019





	Heard on High

**Author's Note:**

> Thank you to Prinz and Kainosite for betaing under challenging circumstances!

Christmas in Gotham was different from Christmas in Metropolis, or Christmas anywhere else in the world. In place of jaunty decorations and the smell of roasting chestnuts and strains of uplifting music announcing goodwill to men, Gotham had a faintly menacing-looking Christmas tree in front of its City Hall. The lights that hung from its rooftops seemed less like a celebration of the season and more a warning of what lurked in the shadows where the brightness didn’t reach. 

Clark had traveled across state lines this evening, to this city where the nights always seemed to be three degrees below freezing and as dark as five minutes to midnight the whole year round. 

Clark Kent had any number of reasons to visit Gotham. Lex’s assistant Mercy Graves had just been sighted getting on the last train bound for Gotham Central, and the Red Hood had recently paid a visit to Metropolis — sources suggested he’d called a truce with the Batman and scaled down his violent proclivities, but a good investigative journalist would always follow an inter-city trail of vigilante crime.

When it came to crime-fighting, however, Superman normally gave Gotham a wide berth. Every member of the League did, out of professional courtesy for their very private colleague who considered this crime-ridden city his home turf. 

This year, Batman had more than his usual share of private business to take care of. The Red Hood vendetta had gone on for months. Also, Talia al Ghul had spent most of the summer at the Waynes’ lake house and when she’d left, she’d left behind a genetically-engineered son trained by the Society of Assassins. 

Nobody had wanted to pry, but when the League had convened at the Manor after Halloween, Diana had not-so-casually mentioned the Batman hadn’t been seen in weeks. It also seemed, for the first time in fifteen years, Bruce Wayne had given the Gotham Philharmonic’s Thanksgiving Gala a miss.

Clark wasn’t worried, exactly. He definitely wasn’t in Gotham to check up on Bruce. The billionaire socialite had the best protection money could buy, and the best investigative journalist in the world wouldn’t think to question Batman’s famous self-sufficiency. 

The incident last Christmas, where Batman’s villains had drugged him to the gills with sex pollen and Kryptonite, and used him as bait for Superman? It was clearly a one-time thing —just another day at the office, saving a coworker from a particularly vicious trap. After they’d made sure that the drug had burned itself out of Bruce’s system and the perpetrators were captured and returned to Arkham Asylum, Batman had vanished into the night without saying another word, as if he was the one with super speed. 

On Christmas Day, an anonymous hamper from Bergdorf’s arrived on Martha Kent’s doorstep. Since then, though, and through the months that followed, there was close to zero contact. 

Clearly Bruce had mixed feelings about what had happened. After all, drugs made people say things they didn’t mean, even people as iron-willed as the Batman. In any case, it seemed Bruce had decided it was best to stay away. 

Clark was going to respect this choice, no questions asked. He wasn’t a naive farm boy any more — he’d saved countless human lives and held down a career at a respected newspaper, he’d found love and fallen out of it, he’d died and come back to life. He could absolutely deal with a friend’s decision, after a night of necessary rescue sex, to move on with his life. 

If he was being totally honest, Clark hadn’t been doing such a great job of moving on with his own life. He hadn’t been on a date in months, and when he touched himself at night, sometimes he couldn’t help picturing Bruce’s face. But that was his problem, not Bruce’s. 

Which was why he was absolutely not here in this city looking to stalk his friend or do anything that might be misinterpreted as stalking. This included heading to that friend’s fancy house and asking Alfred what Bruce had been up to in the months when he hadn’t returned Clark’s calls.

Instead, Clark walked through Gotham, from the train station to the precinct headquarters, down the upscale streets with their slick, stylish holiday displays and fine dining restaurants, and the side lanes where the more lavish store windows and darkened shop-fronts hid the spoils of organised crime.

Finally, he came to a stop in front of City Hall. It was now nearly midnight for real. Only a handful of Gotham citizens remained on the streets, muffled in coats and hurrying on home. It was so cold that even the homeless men who usually populated this square had long since sought refuge indoors. 

Clark looked up at the sky, past the looming Christmas tree and gloomy decorations and the Gothic roof of the town hall, the buildings forming dark outlines against an even darker night. He was wondering whether it was too late to call on Alfred after all, when his enhanced sight caught the edges of something swooping by — a ripple of wings too large to belong to a bird or a bat. 

This called for closer investigation.

Clark got into costume, and took to the air.

From on high, Gotham City looked beautiful but no less oppressive. Wreathed in fog, dimly lit by street lamps below and the pinpricks of stars overhead, her rooftops were remote and forbidding. The bat-signal on top of the police precinct was dark, the GCPD having stood down for the night.

On the roof of the town hall, sheltering against the impassive stone of the graven gargoyle statues, was something else that had wings.

It was man-shaped, but twice the size of a normal man. Its shoulders and barrel chest were covered in a deep pelt of fur, its leathery wings unfolded and spanning a good ten feet across. Its head and pointed ears had swiveled upwards, and its orange eyes locked intently onto his.

 _Kirk Langstrom?_ Clark didn’t recall the Man-Bat being this big, though Langstrom’s continued use of the serum might have resulted in a more extreme mutation than before. 

Langstrom was occasionally a friend and occasionally a foe, his lucid periods depending on how long he’d stayed in his mutated form. Tonight, with his teeth bared and claw-like talons extended, it wasn’t clear which end of the spectrum he was currently on.

Clark descended cautiously, extending his open palms in what he hoped was an unthreatening manner.

“I’m not going to hurt you,” he started to say as he touched down, when the Man-Bat spoke in a familiar voice.

“I should’ve known you wouldn’t stay away.”

This wasn’t Langstrom. The speaker’s vocal cords had been stretched out of their usual shape, but there was no mistaking the distinctive, gravelly tones, like silk over steel.

“Bruce,” Clark said, slowly, unable to hide his surprise. Well, _this_ was a good reason for not attending the Philharmonic’s Thanksgiving Ball.

Now Clark could recognize the distorted contours of his friend’s chiseled face, which the size increase and the fur and the pointed ears had initially masked. He walked cautiously across the rooftop, and Bruce unfurled from the shadows to meet him, oddly graceful despite the additional bulk and strangely-jointed legs. 

He drew his lips back in a caricature of a smile. His mouth was filled with too-sharp teeth. 

“Tim wanted to call you. Alfred said he thought you’d get me to see sense. No need, of course. Everything’s under control.” 

Clark eyed his friend warily. “Nobody called. Sounds like maybe they should have. What have you done to yourself?”

Bruce paused, as if he was weighing telling Clark that what he’d done wasn’t any of Clark’s business, or Superman’s, either. Finally, he settled on, “It isn’t what it looks like,” which at least showed some level of self-awareness. “Talia stole the formula. She wants to create a mutation that’s permanent, so she can fill the Society of Assassins with man-bats. She even tried it on Damian. I’ve been working for weeks on a better antidote, as well as a vaccine.” 

Clark wrestled with a surge of anger. The woman had always been self-obsessed and power-hungry — she was Ra’s al Ghul’s daughter, after all — but to try the formula on a child, let alone one whom she’d engineered from Bruce’s stolen DNA and had raised in a lab, that was taking vileness to another level.

“And you’re using yourself as a test subject? Alfred’s right, you’re not seeing sense. I know you’re worried about Damian, but there’s got to be a safer way to do this.” 

A muscle twitched in Bruce’s jaw, and the orange eyes narrowed in a way that told Clark he’d hit home. Bruce was afraid for the boy, on edge about Red Hood, and taking unnecessary risks. 

“Don’t worry about me, Superman. These test conditions are perfectly safe.”

Bruce’s drawl was light and measured, but Clark wasn’t this easily fooled. The serum was taking its toll on Bruce: his heart was racing, he had to breathe harder, the pressure in his veins and arteries had ramped up fourfold so oxygen could get to all the parts of his massive new body.

He didn’t have to call Bruce on his bluff. The greatest detective in the world didn’t need the Man-Bat’s enhanced senses to read Superman like a book.

“Fine. I will admit the serum does have some effect. But I mean it — everything’s under control. If there was any doubt, I would be locked down in S.T.A.R. Labs and monitored round-the-clock.”

“I’m sure Langstrom thought he had everything under control, too,” Clark said. “Explain to me again why we’re going with the non-lockdown option?”

Bruce’s heart rate leaped before he could get ahold of himself — obviously, he wasn’t as on top of his serum-enhanced emotions as he claimed. Between his teeth, he said, “This iteration of the antidote is at 100% efficacy, though it takes longer to take effect. And — this might come as a surprise to you — I just wanted to get some fresh air; I’ve been cooped up in that lab for weeks. Tim volunteered to be my backup test subject, but I’m not risking the serum on anyone else.”

On the topic of test subjects, Clark wondered whether the man-bat serum would work on Superman, and then decided nobody needed to see what the giant Kryptonian bat version might look like. Firmly, he said, “So are you planning on staying like this all night, or are you going to take the antidote eventually?”

Bruce’s characteristic sneer made his man-bat face momentarily hideous. “Of course I’m going to take it. But there are some benefits to being in this form. Parts of it are almost enjoyable.” He paused, then let out a short bark of laughter. “Listen to me! No wonder Alfred thinks I’m losing my mind.” 

Clark considered this. As far as he could tell, Bruce’s physiological functions still seemed relatively stable. After the challenges of the year, a psychiatrist might suggest various reasons why the Batman might want to leave his burdens behind, together with his handsome human face and his guardian’s armor, and become someone else for a while.

“Well, you sound sane enough to me,” he said, a peace offering, before he added, “You want company?”

Bruce lips twitched. “Are you sure you’re not offering because you think Man-Bat needs Superman to play nursemaid? You haven’t exactly been leaving your calling card, Clark, so I surmised you weren’t interested in company.” 

Clark heard his friend’s pulse speed up, saw the involuntary tension leap through his muscles, but it took him another moment to understand what Bruce was saying. When realization finally dawned, it took his breath away, which took some doing, seeing as Superman didn’t actually need to breathe.

“Hey, you never called _me_!”

Bruce shrugged. “I sent your mom a Christmas present?”

“You didn’t sign the card!”

“I didn’t mean to. Anyway, you knew it was me.”

“I did.” Clark made himself speak calmly. This was the first real conversation they’d had all year, he needed not to mess up. “I left word with Alfred, but you didn’t call back, and then the first Red Hood killings happened, and I figured you needed the space to focus on Jason.” 

He paused to take a deep, steadying breath. “Which somehow became figuring you needed the space from _me_. Because of what happened between us last year.”

Bruce remained silent. His orange eyes were deeply unnerving, as was the lack of expression on his distorted face. Clark turned away so he didn’t have to meet that gaze, continuing, stonily, “I understand that you wanted to move on. No hard feelings, Bruce. Friends only become lovers in comic books.” 

He heard Bruce let out another snort of laughter, and his friend said, thoughtfully, “Sometimes I think we belong in comic books ourselves, the ones meant for kids. Tim definitely thinks I’m acting like I’m Damian’s age about you.” 

Clark looked up, and Bruce reached a clawed hand to curve around his cheek.

“I don’t want to move on from you. I haven’t stopped thinking about you all year. When it wasn’t Jason, or Talia, or Damian, it’s been you.” 

Clark’s own heart began to race. He stared into his friend’s strange eyes, hearing the roar of blood as it coursed through Bruce’s enhanced body, setting off a chain of different organic reactions. Clark wasn’t sure Langstrom had ever given off pheromones in his man-bat form, but the Batman was definitely secreting something that would have astounded the techs at S.T.A.R. Labs.

Clark didn’t think bat pheromones worked on Kryptonian biology, but his chemistry with Bruce Wayne had never needed artificial assistance. He put his hand over Bruce’s, and saw the touch register in that altered but familiar face.

“I think about you all the time,” he confessed. 

Bruce made an inhuman sound and wrapped his huge arms around Clark’s waist. In this form, he was much taller than Superman. Clark began to laugh as he was lifted off his feet: “Except maybe not like this!”

“Yeah, this,” Bruce said. He began to laugh too. “It must be quite the mood killer.”

“I can handle it,” Clark said softly, and leaned up to kiss him.

It was strange enough kissing the Batman; it was all-out bizarre to be kissing this larger version of him that had a snout and a too-sharp bite. Still, somehow, Clark didn’t care. It was Bruce he was kissing: the one person who shared his burdens, the friend whom he’d fought alongside, the man he’d thought about at night through these last solitary months — now Clark finally had him in his arms, he wasn’t going to let a small thing like man-bat serum get in his way.

In spite of how strange it was, the kissing was becoming heated, with the unnatural edge of Bruce’s teeth and the press of Bruce’s wet, damp fur against his skin. Maybe it was the months of deprivation, or maybe the man-bat pheromones were on a long delay, but Clark was getting really hard, a fact which Bruce’s new senses couldn’t fail to detect. That worked both ways: Bruce had had the decency to wear pants in his man-bat form, the same as Langstrom, but the cloth did nothing to conceal the giant erection that had arisen underneath it. Bruce ground himself slowly against Clark’s dick as he kissed him, and it felt so good that Clark groaned out loud.

Bruce pulled off, panting hard. “Damn it. Is this too weird for you? We’ve had a strange enough year as it is. Hang on, let me first take this.” 

Clark watched as Bruce shot himself up with a syringe that contained the S.T.A.R. Labs antidote. The slide of those gigantic muscles under thick fur should absolutely not be so arousing. He felt almost dizzy from the smell rising from Bruce’s body and the almost-animalistic taste on his tongue. 

“I’m not worried. I’ll take you any way I can.”

“That’s nice. It’s also unexpectedly freaky. I wasn’t aware Clark Kent was into this particular kink.”

“Don’t let the Kansas farm boy shtick fool you,” Clark said, running his hands over the heavy pelt of fur across Bruce’s chest. “I’d say I’d be into most things involving the Batman.”

“Really.” Bruce smiled the be-snouted version of his crooked smile, which was starting to grow on Clark. “Even when one of those things is a penis with spines that can grow to eight point four per cent of body mass?”

“No kidding,” Clark said, which was the cue for Bruce to open his pants and demonstrate.

The cock he pulled out was indeed enormous. Jutting from the thick tufts of fur between Bruce’s thighs and above huge, leathery balls, it was as long as Clark’s forearm, and decorated with short, flexible spikes that slanted backwards from the tip like the fletching on an arrow. 

“You really weren’t joking about the spikes, were you.” Clark took hold, and ran a curious hand up and down its length. The spikes were as hot and hard as the shaft of the massive penis, though they had more give to them, and were edged at the ends in a way that would have pierced skin that wasn’t Superman’s. 

“Would I joke about something like this?” Bruce said tersely, though he didn’t pull away. “I said I didn’t want to hurt you the last time, but in this form I actually could.” 

Clark remembered that last time, which had also been their first: Bruce, drugged and half out of his mind with lust, but entirely human, without these wings and teeth and backward-facing penis spines. 

“Not going to happen,” he said, massaging the sharp, springy protrusions, testing their heft and hardness. “Not unless these spikes are made of Kryptonite.”

“Keratin, apparently.” Bruce said tersely, and a little distractedly, as Clark began, very slowly, to stroke. “It seems they get even bigger in the run-up to the mating season.” 

“Seems rough on the bats. Why would they need the spikes?” 

Bruce’s voice was getting rougher. “One theory is that they need them to stay coupled while mating in the air. It’s called the in-flight locking hypothesis. The spikes face backwards, like parking lot spikes, so the penis goes in easily, and then they lock it in place so it can’t slide out again.”

Clark continued to stroke the spiky cock intently, watching as fluid started to leak from the slit at the tip of its swollen, purple head. The smell made his mouth water. “For someone so ready to mock my kink, you’ve been doing a lot of in-depth research.”

“I’ve had some time on my hands,” Bruce murmured. He put his arms around Clark’s shoulders. “Did you know that bats are the only mammals that fly?”

Clark could absolutely not help himself. “Not the _only_ mammals,” he said, meaningfully, and swept his friend into his arms, and they soared up into the night sky.

Bruce let out a whoop as they rocketed past buildings and water-tanks, Gothic rooftops and skyscrapers, into the rim of clouds that blanketed Gotham’s skyline. Then, as they broke through the cloud cover, he extended his new leathery wings to their fullest span, and for the first time in the years they’d known each other, Clark let Bruce take charge of their flight.

Was this how Bruce had always felt in Superman’s embrace, trusting in his superhuman abilities to keep both of them from falling? It was surprisingly freeing. Clark hung on as they careened through the night, the Man-Bat’s strength holding him up, feeling the powerful, muscular beating of wings spread all around them, keeping time with his own urgent heart. 

Finally their headlong flight slowed to a glide, with Bruce’s wings doing the minimum to maintain lift. This high up, the night air was crisp and clean, the stars so much brighter this far away from the city. 

Bruce’s eyes seemed equally bright. “I can see why you like this,” he said. “Up here, everything’s somehow easier.”

“Fresh air does make it seem that way,” Clark agreed, absently. His blood was racing, and so was Bruce’s, arousal an insistent rhythm between their bodies. “You said the new antidote’s slower-acting than the old version — how slow would that be, exactly?”

“Slow enough for whatever you have in mind,” Bruce drawled, and that was the last straw. Clark had spent the better part of a year trying to get over this man, and here Bruce was at last, offering what Clark had been too blind or stubborn to see before. He grasped it now, winding his legs around Bruce’s and making no secret of what he wanted.

“Want to test that in-flight locking hypothesis?” 

Bruce snorted with laughter. “Fine. Anything for science.” 

Bruce’s sharp claws helped Clark make short work of Superman’s costume. Then Clark was lifting his hips for Bruce, hard and insistent and — thanks to the Codex which he carried within him — dripping wet.

Despite everything, Bruce hesitated. With its huge fur-covered muscles and spiky penis, this Man-Bat form seemed more alien than anything that had come from Krypton’s orbit. 

“Come on,” Clark said, reassuringly; “I told you, you can’t actually hurt me,” and Bruce spread his wings and hooked an arm around Clark’s waist and thrust his massive length into Clark’s ass.

Clark cried out; for a second, he forgot how to breathe. Phosphenes went off behind his eyes, momentarily obscuring his enhanced vision. Bruce’s enormous dick crammed into every inch of him, the long spines scraping down Clark’s invulnerable walls, until they finally locked into place, and claimed him completely at last.

“Clark? Are you —?”

“I’m fine,” Clark gasped. He’d never felt this full before, not even the first time Bruce had fucked him, the stretch and burn as he opened around the enhanced girth and its new protrusions so intensely pleasurable it was almost agony. The spines dug in so deeply it almost felt as if they could pierce even Superman’s impenetrable flesh. “Better than fine. We should let the scientists know their theories could be wrong, the spines are for _pleasure_ —” 

“Goddamnit, Clark, I was kidding about this being for science,” Bruce sighed, and he began to thrust into Clark in earnest. 

Clark had never had sex while flying before, but he could see why bats risked their lives to mate in flight. Spiraling up through the air, couples had nothing to use for leverage except each other’s bodies and gravity — clinging tightly together, they had to grapple with each other for hold and ballast, pushing up against the other and twisting in mid-air, taking turns to rise and fall, to thrust and then thrust back. 

Securely locked in place, Bruce rocked back and forth inside Clark’s body in short, powerful strokes, trying to find a rhythm. Clark wrapped his limbs around Bruce’s sweating, fur-covered ones and rode the twists and turns of this unpredictable tempo. The sensation of spikes dragging across Clark’s passage as Bruce thrust in deeper, yielding and then springing back again, was incredible; from the noises that spilled from Bruce’s lips, it sounded like the spikes were as enjoyable for the giver as they were for the recipient. 

Bruce began to pulse his wings again powerfully, and once more they climbed into the sky, both of them bucking and thrusting and fighting for purchase against each other.

“Sometimes mating bats fall to their deaths,” Bruce groaned. His veins were dilated, his muscles were trembling, he was losing control. The self-discipline that had for so long held Langford’s insanity at bay was now being consumed by this act of love. 

“Yeah, but what a way to go,” Clark tried to say, though his words were failing him. He’d waited so long for this, they both had, but he couldn’t last for much longer, either. 

He could see his orgasm approaching from across the bowl of the sky. He couldn’t hold on, and as they plummeted helter-skelter down through the clouds, toward the dark city below, he plunged head-first over that final horizon. 

Clark abruptly returned to himself just before they hit the ground. Folding Bruce into his arms, he swept them both back into the air in a slow, careful arc across the sky. 

Their headlong descent must have finally accelerated the antidote’s effectiveness. The man he held was fully human again, his sweat-slick flesh smooth against Clark’s own, the softening prick sliding out of Clark’s ass without the spikes to lock it in place.

It was Clark’s turn to ask. “Are you okay?”

“Yeah. Thanks for the save. And for everything else.” Bruce’s voice was unsteady from the transformation, or maybe it was just the sex. In any case, he’d never have admitted to needing help from anyone other than Superman.

Clark peered into his friend’s familiar, handsome face. Bruce might as well be wearing his mask for all that could be seen in his expression, but Clark could tell how much conflict there was going on underneath.

“Are we done with not talking to each other?” he asked. “I mean, I want you to have the space you need, but I feel what you need now isn’t more space from me.” 

Bruce was silent as they drifted through the air. Clark wrapped his arms more tightly around his friend and started to descend — he could tell that without the thick pelt of fur, Bruce was starting to get cold.

Finally, Bruce said, “And what about what _you_ need? Superman’s life is complicated enough without the Batman’s extra cargo.”

Clark tried not to roll his eyes. “We’ll work it out. We always have. Despite your willingness to turn yourself occasionally into a giant bat.” 

Bruce dug his chin into Clark’s chest. “Didn’t hear you complaining. In fact, maybe I’ll bring the serum the next time we’re in bed.”

Clark felt himself flush, and then laughter bubbled up through him like the champagne Bruce Wayne preferred. Batman was himself once more, and Bruce was prepared for there to be a next time, and for now, that was good enough for Clark.

“Now you’re not judging my kink,” he murmured, and they coasted over the darkened rooftops of Gotham City, heading for home.

**Author's Note:**

> Navaan’s prompt this year was _Above the roofs of my city_. Bet she didn’t quite expect these goings-on ;) 
> 
> [Details](https://www.google.com.sg/amp/s/slate.com/technology/2013/10/bizarre-bat-behavior-oral-sex-pollinating-tequila-sharing-meals-drinking-blood-males-lactating.amp) about [bat reproductive behaviour](http://www.bbc.com/earth/story/20150912-why-some-male-bats-have-spines-on-their-penises). 
> 
> [Mat-Bat serum backstory](https://en.m.wikipedia.org/wiki/Man-Bat#/media/File%3AMan-Bat.jpg).
> 
> [Man-Bat working out his daddy issues with Batman’s son-designate](http://www.gothamcalling.com/wp-content/uploads/2019/04/batman-361.jpg).
> 
> Plot-line with Talia, Damian and the Man-Bat serum vaguely taken from [here](https://en.m.wikipedia.org/wiki/Batman_and_Son).


End file.
